Protostar curved secondary holders

Hi all,
I'm looking for opinions and user reports of the Protostar curved vane
secondary holders. I'm building an 8" f/6 with a round fiberglass tube and
a wall thickness of 1/8".

I have used a Protostar 3-vane spider in the past and would definitely use
one again based on it's quality and ability to hold collimation even after
years of transporting the scope.

I've been out of the ATM hobby since these curved vane holders came onto the
market so any info would be appreciated.

Bill Cotten
www.spokaneastronomical.org

On Mon, 13 Jun 2005 19:24:06 -0700, "Bill Cotten"
wrote:

Hi all,
I'm looking for opinions and user reports of the Protostar curved vane
secondary holders. I'm building an 8" f/6 with a round fiberglass tube and
a wall thickness of 1/8".

I have used a Protostar 3-vane spider in the past and would definitely use
one again based on it's quality and ability to hold collimation even after
years of transporting the scope.

I've been out of the ATM hobby since these curved vane holders came onto the
market so any info would be appreciated.

Bill Cotten
www.spokaneastronomical.org



If you'd rather see an image that looks like you are looking
though a cracked objective lens than one with traditional diffraction
spikes, it's a good thing to go for.
-Rich

On Mon, 13 Jun 2005 19:24:06 -0700, "Bill Cotten"
wrote:

Hi all,
I'm looking for opinions and user reports of the Protostar curved vane
secondary holders. I'm building an 8" f/6 with a round fiberglass tube and
a wall thickness of 1/8".

I have used a Protostar 3-vane spider in the past and would definitely use
one again based on it's quality and ability to hold collimation even after
years of transporting the scope.

I'm sure they will function as most curved vanes do if kept reasonably
thin: no diffraction spikes, but instead a dim glow around bright
objects. That's how my own .5mm thick curved vane performs.

Dan chaffee

Personally I dont like em. Prefer the old fashioned straight vanes with
the stellar diff lines the GenX-ers are now trying to emulate synthetically,
along with dreams of social security and health care!





Bill Cotten wrote:

Hi all,
I'm looking for opinions and user reports of the Protostar curved vane
secondary holders. I'm building an 8" f/6 with a round fiberglass tube and
a wall thickness of 1/8".

I have used a Protostar 3-vane spider in the past and would definitely use
one again based on it's quality and ability to hold collimation even after
years of transporting the scope.

I've been out of the ATM hobby since these curved vane holders came onto the
market so any info would be appreciated.

Bill Cotten
www.spokaneastronomical.org

"Bill Cotten" wrote in message
...
Hi all,
I'm looking for opinions and user reports of the Protostar curved vane
secondary holders. I'm building an 8" f/6 with a round fiberglass tube and
a wall thickness of 1/8".

I have used a Protostar 3-vane spider in the past and would definitely use
one again based on it's quality and ability to hold collimation even after
years of transporting the scope.

Hi all,
Thanks for the responses. Based on what I've read here, elsewhere and
experience, I'll use a 3 vane Protstar for the new scope. At f/6 it will be
used more for deep sky. I'll stick with an 8" f/8 Cave Astrola for planetary
viewing.
Bill Cotten